Highlights
- Updated Mineral Resource confirms a large tonnage of high-grade lithium-boron mineralisation from surface
- Resource well suited for open pit mining at low strip ratios
- High-grade portion of the Indicated and Inferred Resource doubled from 65 to 137 million tonnes at 1,800ppm lithium (equivalent to 0.9% lithium carbonate) and 1.26% boron (equivalent to 7.2% boric acid)
- Total Resource (Indicated and Inferred) of 460 million tonnes at 1,700ppm lithium (equivalent to 0.9% lithium carbonate) and 0.46% boron (equivalent to 2.6% boric acid)
- Total Resource contains lithium and boron equivalent to 4.1 million tonnes of lithium carbonate and 11.9 million tonnes of boric acid
- High-grade lithium-boron mineralisation is the focus of the Pre-Feasibility Study as it provides potentially higher value per tonne and a low-cost, simple processing route
SYDNEY, Australia, Oct. 31, 2017 (GLOBE NEWSWIRE) -- Australian-based mineral explorer and developer Global Geoscience Limited (“Global” or the “Company”) (ASX:GSC) is pleased to announce an updated Mineral Resource Estimate for its 100%-owned Rhyolite Ridge Lithium-Boron Project (“Rhyolite Ridge” or the “Project”) in Nevada, USA.
The Indicated and Inferred Resource for the South Basin at Rhyolite Ridge is now estimated to total 460 million tonnes at 1,700ppm lithium (equivalent to 0.9% lithium carbonate) and 0.46% boron (equivalent to 2.6% boric acid).
The high-grade lithium-boron component of the Resource is estimated at 137 million tonnes at 1,800 ppm lithium (equivalent to 0.9% lithium carbonate) and 1.26% boron (equivalent to 7.2% boric acid), with 75% of the Resource in the Indicated category. This represents a doubling of the 2016 estimate of the high-grade component.
The high-grade lithium-boron mineralisation is the focus of the Pre-Feasibility Study (”PFS”) as it represents potentially the highest value material combined with a low-cost, simple processing route. This is due to the low-clay, low-carbonate and high-searlesite content of the rock, which make the mineralisation amenable to low-cost acid leaching at ambient temperature and pressure.
Global’s Managing Director, Bernard Rowe commented: “This updated Mineral Resource clearly demonstrates the significant scale and quality of the Rhyolite Ridge lithium-boron deposit. We are continuing to rapidly advance the project with mining studies and metallurgical test work as part of the current PFS process. The RPM led mining study is focusing on the high-grade lithium-boron mineralisation as it represents the potentially highest value, lowest processing cost option.”
The Resource remains open to the north, south and east and has significant potential to expand with further drilling of the South Basin. Not included in the Mineral Resource estimate is known lithium-boron mineralisation in the North Basin at Rhyolite Ridge.
Mineral Resource Statement and Parameters
The updated Indicated and Inferred Resource estimate for the South Basin at Rhyolite Ridge totals 460 million tonnes at 0.9% lithium carbonate and 2.6% boric acid (at a 1,050ppm Li cut-off).
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The Indicated and Inferred Resource includes a high-grade lithium-boron zone totaling 137 million tonnes at 0.9% lithium carbonate and 7.2% boric acid (at a 1050ppm Li and 0.5% B cut-off).
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Notes to the above Mineral Resources tables:
1. Totals may differ due to rounding, Mineral Resources reported on a dry in-situ basis.
2. The Statement of Estimate of Mineral Resources has been compiled by Mr. Robert Dennis who is a full-time employee of RPM Advisory Services Pty Ltd (“RPM”) and a Member of the AIG and AusIMM. Mr. Dennis has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity that he has undertaken to qualify as a Competent Person as defined in the JORC Code (2012).
3. All Mineral Resources figures reported in the table above represent estimates at 19 October 2017. Mineral Resource estimates are not precise calculations, being dependent on the interpretation of limited information on the location, shape and continuity of the occurrence and on the available sampling results. The totals contained in the above tables have been rounded to reflect the relative uncertainty of the estimate. Rounding may cause some computational discrepancies.
4. Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code – JORC 2012 Edition).
6. Reporting cut-off grade of 1,050ppm Li selected based on an RPM cut-off calculator assuming an open pit mining method, a US$8,000/t Li2CO3 price, a 90% metallurgical recovery for Li2CO3 and costs derived from a high level technical report supplied by independent processing consultants to Global Geoscience. Within the Resource defined at 1,050ppm Li a subset defined at 0.5% B has been reported to quantify a portion of the resource high in Li and B which is the target of possible early production. The relationship between the two styles of mineralisation is illustrated in Figures 3 and 4.
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Summary of Resource Estimate Parameters and Reporting Criteria
In accordance with ASX Listing Rules and the JORC Code (2012 Edition), a summary of the material information used to estimate the Mineral Resource is detailed below (for further information please refer to Table 1 in Appendix 1).
- The Rhyolite Ridge Mineral Resource area extends over a north-south strike length of 2,870m (from 4,183,750mN – 4,186,620mN), has a maximum width of 2,030m (423,730mE – 425,760mE) and includes the 550m vertical interval from 1,960mRL to 1,410mRL.
- The Rhyolite Ridge Project tenements (unpatented mining claims) are owned by Paradigm Minerals Arizona Corporation, a company wholly owned by Global Geoscience Ltd. The unpatented mining claims are located on US federal land administered by the Bureau of Land Management (BLM).
- A site visit was conducted by John Zeise of RPM, a representative of the Competent Person for Mineral Resources, during September 2016. The site visit included inspection of the geology, drill core and the topographic conditions present at the site as well as infrastructure. During the site visit, Mr Zeise had open discussions with Global Geoscience’s personnel on technical aspects relating to the relevant issues and in particular the geological data.
Geology and Geological Interpretation
- Lithium, boron and potassium mineralisation is stratiform in nature and is hosted within Tertiary-age carbonate-rich sedimentary rock, deposited in a basin environment in the Basin and Range terrain of Nevada, USA.
Drilling Techniques and Hole Spacing
- Drill holes used in the Mineral Resource estimate included 19 trenches, 42 RC holes and 24 diamond holes for a total of 8,952m within the defined mineralisation. The full database contained records for 85 drill holes for 15,802m of drilling and trenching.
- All drill hole collars have been surveyed to the UTM Zone 11 NAD27 grid system. For previous owners/operators, collars were survey by a contract surveyor utilising a GPS device. Holes drilled by Global Geoscience were surveyed by DGPS.
- No down hole surveys were conducted for the trenches or RC holes, therefore nominal surveys were designated. Down hole survey methodology for the diamond drilling was not recorded, however readings were conducted on approximate 30m intervals down hole.
- Drill hole spacing is 200m by 200m (or less) over most of the deposit. Spacing increases to approximately 200m by 300m along the eastern margin of the deposit.
- Drill holes were logged for a combination of geological and geotechnical attributes. The core has been photographed and measured for RQD and core recovery.
Sampling and Sub-Sampling Techniques
- Drilling was conducted by American Lithium Minerals Inc., the previous owner of the tenements between 2010 and 2011 and by Global Geoscience in 2017. For RC drilling, a 5 inch hammer with crossover-sub was used with sampling conducted on 1.52m intervals and split using a rig mounted rotary splitter. The hammer was replaced with a tri-cone bit in instances of high water flow. For diamond core, HQ core size diameter with standard tube was used. Core recoveries of 97% were achieved at the project. The core was sampled as half core at 1.52m intervals using a standard electric core saw.
Sampling Analysis Method
- Samples were submitted to ALS Chemex Laboratory in Reno, Nevada for sample preparation and analysis. The entire sample was oven dried at 105˚ and crushed to -2 mm. A sub-sample of the crushed material was then pulverised to better than 85% passing -75µm using a LM5 pulveriser. The pulverised sample was split with multiple feed in a Jones riffle splitter until a 100-200g sub-sample was obtained for analysis.
- Analysis of the samples was conducted using aqua regia 2-acid and 4-acid digest for ICP-MS on a multi-element suite. This method is appropriate for understanding sedimentary lithium deposits and is a total method.
- Standards for Li, B, Sr and As and blanks were routinely inserted into sample batches and acceptable levels of accuracy were reportedly obtained. Overall, QAQC results deemed all assay data suitable and fit for purpose in Mineral Resource estimation.
Cut-off Grades
- The Mineral Resource has been reported at a 1,050ppm lithium cut-off. The cut-off was selected based on an RPM cut-off calculator assuming an open pit mining method, a US$8,000/t Li2CO3 price, a 90% metallurgical recovery for Li2CO3 and costs derived from a high level technical report supplied by independent processing consultants to Global Geoscience and metallurgical test work results reported by Global Geoscience. Within the 1,050ppm lithium cut-off domain a sub-domain set at a cut-off of 0.5% boron was reported to define a zone of lithium-boron rich mineralisation within the Mineral Resource. The presence of boron associated with lithium is considered favourable as the mineralisation potentially has higher value and, based on studies by Global Geoscience, has potentially lower processing costs and capital requirements.
Estimation Methodology
- Samples were composited to 1.52m based on an analysis of sample lengths inside the wireframes. After review of the project statistics, it was determined that high grade cuts for B within three mineralised domains was necessary. The cuts applied ranged between 300ppm and 11,000ppm B, resulting in 79 composites being cut.
- The block dimensions used in the model were 100m N-S by 50m E-W by 5m vertical with sub-cells of 6.25m by 6.25m by 1.25m. This was selected as the optimal block size as a result of kriging neighbourhood analysis.
- Ordinary kriging grade interpolation was used for the estimate, constrained by Mineral Resource outlines based on mineralisation envelopes prepared using a nominal 1,000ppm Li cut-off grade with a minimum down-hole length of 3m. For internal high grade B zones, a nominal 5,000ppm B cut-off grade was used. Up to four passes were used to estimate the blocks in the model and more than 99% of blocks were filled in the first two passes.
- A total of 137 bulk density measurements were taken on core samples collected from diamond holes drilled at the Project using the water immersion technique. Bulk densities ranging between 1.8t/m3 and 2.11t/m3 were assigned in the block model dependent on mineralisation and lithology.
Classification Criteria
- The Mineral Resource was classified as Indicated and Inferred Mineral Resource based on data quality, sample spacing, and lode continuity. The Indicated Mineral Resource was defined within areas of close spaced diamond and RC drilling of less than 200m by 200m, and where the continuity and predictability of the mineralised units was good. The Inferred Mineral Resource was assigned to areas where drill hole spacing was greater than 200m by 200m and less than 400m by 400m.
Mining and Metallurgical Methods and Parameters
- Based on the relatively low angle dips, thicknesses and depths of the mineralised bodies that have been modelled, as well as their estimated grades, the potential extraction method is considered to be open pit mining. However, no mining optimisation has been completed at this stage.
- There are two types of mineralisation present: 1) lithium-boron mineralisation that is low in clay content and low-moderate in carbonate content and 2) lithium-only mineralisation that has higher clay content and moderate to high carbonate content. The lithium content of both types is similar however the lithium-boron mineralisation averages over 1% boron making it potentially higher value material.
- Global Geoscience is focussing its evaluation and test work on the lithium-boron mineralisation as it potentially is of higher value with lower processing and capital costs.
- Based on test work completed for Global Geoscience by Hazen Research of Colorado, USA and SGS Minerals of Ontario, Canada and reported by Global Geoscience both the lithium-boron and lithium-only mineralisation have a reasonable expectation of economic extraction. Prices, costs and recoveries were obtained from a high level technical report and discussions regarding the ongoing test work supplied by independent processing consultants to Global Geoscience.
- Metallurgical test work has been conducted on drill core and outcrop samples and shows that the lithium-boron mineralisation is amenable to acid leaching (sulphuric). Global Geoscience has reported recoveries from acid leaching in the range of 85% to 98% for lithium and boron. Further test work is required to establish total recoveries to produce end products.
Comparison with Previous Mineral Resources
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Contacts at Global Geoscience
Bernard Rowe | James D. Calaway | Roger Howe |
Managing Director | Chairman | Investor Relations |
T: +61 419 447 280 | T: +1 713 818 1457 | T: +61 405 41 9 139 |
E: browe@globalgeo.com.au | E: jcalaway@calawayinterests.com | E: rhowe@globalgeo.com.au |
About Global Geoscience
Global Geoscience Limited (ASX:GSC) is an Australian-based mineral explorer and developer focused on its 100%-owned Rhyolite Ridge Lithium-Boron Project in Nevada, USA. Rhyolite Ridge is a large, shallow lithium-boron deposit located close to existing infrastructure. It is a unique sedimentary deposit that has many advantages over the brine and pegmatite deposits that currently provide the world’s lithium. The Rhyolite Ridge Pre- Feasibility Study is well under way.
Global Geoscience is aiming to capitalise on the growing global demand for lithium and boron. Lithium has a wide variety of applications, including pharmaceuticals, lubricants and its main growth market, batteries. Boron is used in glass and ceramics, semiconductors and agriculture. Global Geoscience aims to develop the Rhyolite Ridge Lithium-Boron Project into a strategic, long-life, low-cost supplier of lithium carbonate and boric acid. To learn more please visit: www.globalgeo.com.au.
Competent Persons Statement
The information in this report that relates to Mineral Resources is based on information compiled by Mr Robert Dennis who is a Member of the Australasian Institute of Geoscientists and the Australian Institute of Mining and Metallurgy. Mr Dennis is a full time employee of RPM Advisory Services Pty Ltd. Mr Dennis is the Competent Person for this Mineral Resource estimate and has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he has undertaken to qualify as a Competent Person as defined in the 2012 Edition of the ‘Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves’. Mr Dennis consents to the inclusion in this report of the matters based on his information in the form and context in which it appears.
Appendix 1 – Rhyolite Ridge Lithium-Boron Project, Nevada, USA
JORC Code, 2012 Edition – Table 1
Section 1 Sampling Techniques and Data
Criteria | JORC Code explanation | Commentary |
Sampling techniques |
| Drilling was conducted by American Lithium Minerals Inc., the previous owner of the tenements between 2010 and 2011 and by Global Geoscience in 2017. For RC drilling, a 5 inch hammer with cross-over sub was used with sampling conducted on 1.52m intervals and split using a rig mounted rotary splitter. The hammer was replaced with a tri-cone bit in instances of high water flow. For diamond core, HQ core size diameter with standard tube was used. The core was sampled as half core at 1.52m intervals using a standard electric core. The entire sample was crushed then split and a sub-sample pulverised to produce a sample for multi-element analysis by aqua regia ICP-MS. |
Drilling techniques |
| RC drilling was conducted using a 5 inch hammer with cross-over sub. Diamond core was conducted using HQ core diameter with standard tube. |
Drill sample recovery |
| Diamond core recovery was reported to be 97%. Recoveries were not recorded for historical RC drilling. It was reported that the grades in RC holes were less than in the equivalent intervals in core holes. This was particularly evident in deeper intervals and is probably explained by loss of fines due to ground water depth. For RC drilling undertaken by Global Geoscience:
|
Logging |
| All holes have been geologically and geotechnically logged over their entire length to a level of detail sufficient for a Mineral Resource estimation. The logging is qualitative in nature. All core was photographed. |
Sub-sampling techniques and sample preparation |
| For diamond holes, samples comprise wet sawn half-core. For historical RC holes, samples were collected using a wet rotary splitter. Two samples were collected for every interval – one sample and one duplicate. For Global Geoscience RC holes, samples were wet split using a rotary splitter attached to a cyclone and duplicate samples were collected every 20th sample. The nature, type and quality of the sample preparation technique is considered appropriate. Samples are considered representative of the in-situ rock. Quality control measures included the routine insertion of standards and duplicates. Results were reported to be satisfactory. The sample sizes are considered to be appropriate. |
Quality of assay data and laboratory tests |
| Samples were analysed by ALS Chemex in Reno, Nevada using 2-acid and 4-acid digestion and ICP mass spectrometry. The methods and procedures are appropriate for the type of mineralisation and the techniques are considered to be total. Standards for Li, B, Sr and As and blanks were routinely inserted into the sample batches. Acceptable levels of accuracy were reportedly obtained. |
Verification of sampling and assaying |
| Significant intersections have been independently verified by at least two company personnel. Data is stored in digital format in a database. Several RC holes have been twinned with core holes and the results were satisfactory. There has been no adjustment to assay data. |
Location of data points |
| Historical drill hole locations were measured by GPS and are accurate to within 2m. Collars are marked on the ground with a permanent concrete marker. Global Geoscience drill hole locations were measured by DGPS and are accurate to within 1m. The area of drilling and hole coordinates are shown in UTM Zone 11, NAD27 grid system. |
Data spacing and distribution |
| Drill holes were generally spaced at 100-300m. The spacing is considered sufficient to establish geological and grade continuity appropriate for a Mineral Resource estimation. No sample compositing has been applied. |
Orientation of data in relation to geological structure |
| Drill holes were angled at between -60 and -90 degrees. The holes intersected the mineralisation at between 70 and 90 degrees. The orientation is considered appropriated and provides unbiased sampling of the mineralisation. |
Sample security |
| For historical holes, samples were collected from site by ALS Chemex. Chain of custody forms were maintained by ALS Chemex. For Global Geoscience holes, samples were securely stored on-site and then collected from site by ALS and transported to the laboratory by truck. |
Audits or reviews |
| RPM reviewed core and sampling procedures during the 2016 site visit and found that all procedures and practices conform to industry standards. |
Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)
Criteria | JORC Code explanation | Commentary |
Mineral tenement and land tenure status |
| The Rhyolite Ridge Project tenements (unpatented mining claims) are owned by Paradigm Minerals Arizona Corporation, a company wholly owned by Global Geoscience Ltd. The unpatented mining claims are located on US federal land administered by the Bureau of Land Management (BLM). There are no known private royalties over the claims. There are no known impediments to exploration or mining in the area. |
Exploration done by other parties |
| At least two campaigns of modern lithium-boron exploration are known at the project. In the 1980's US Borax surface sampled and drilled a basin of lithium and boron-rich sediments over a 2km by 1km area. The area was known as the North Borate Hill project. In total, US Borax completed 57 holes totalling about 15,000m. The work was primarily focussed on boron mineralisation and the lithium mineralisation was largely ignored. In addition to the exploration completed at North Borate Hill, US Borax also drilled 12 holes at South Borate Hill where they described higher lithium values. In 2010-2011 American Lithium Minerals Inc and Japan Oil, Gas and Metals National Corporation (JOGMEC) conducted further lithium exploration in the south basin area. The exploration included at least 465 surface and trench samples and 36 drill holes. The Company has access to the American Lithium data including all drill holes and drill core. |
Geology |
| Lithium, boron and potassium mineralisation is hosted within Tertiary-age carbonate-rich clay sediments, deposited in a basinal environment in the Basin and Range terrain of Nevada, USA. |
Drill hole information |
| Exploration Results are not being reported. The information relating to exploration results from drilling used in the Resource Estimation has been disclosed by Global Geoscience in previous ASX announcements. |
Data aggregation methods |
| Exploration Results are not being reported. Not applicable as a Mineral Resource is being reported. Not applicable as no metal equivalent values are being reported. |
Relationship between mineralisation widths and intercept lengths |
| Drilling intersected mineralisation at approximately 70 to 90 degrees. |
Diagrams |
| Relevant diagrams have been included within the Mineral Resource report main body of text. |
Balanced Reporting |
| The report is believed to include all representative and relevant information and is believed to be comprehensive. Exploration results are not being reported. |
Other substantive exploration data |
| No other information is available at this time. Metallurgical testwork undertaken by GSC has indicated that the lithium-boron mineralisation is amenable to acid leaching (sulphuric). |
Further work |
| Further work will include:
|
Section 3 Estimation and Reporting of Mineral Resources
Criteria | JORC Code explanation | Commentary |
Database integrity |
| Geological and field data is collected using customised Excel logging sheets on tablet computers. The data is verified by company geologists before the data is imported into an Access database. RPM performed initial data audits in Surpac. RPM checked collar coordinates, hole depths, hole dips, assay data overlaps and duplicate records. Minor errors were found, documented and amended. |
Site visits |
| A site visit was conducted by John Zeise of RPM, a representative of the Competent Person for Mineral Resources, during September 2016. The site visit included inspection of the geology, drill core and the topographic conditions present at the site as well as infrastructure. During the site visit, Mr Zeise had open discussions with Global Geoscience’s personnel on technical aspects relating to the relevant issues and in particular the geological data. |
Geological interpretation |
| The confidence in the geological interpretation is considered to be good and is based on visual confirmation in outcrop and drilling. Geochemistry and geological logging has been used to assist identification of lithology and mineralisation. There are two types of mineralisation present: 1) lithium-boron mineralisation that is low in clay content and low-moderate in carbonate content and 2) lithium-only mineralisation that has higher clay content and moderate to high carbonate content. The lithium content of both types is similar however the lithium-boron mineralisation averages over 1% boron making it potentially higher value material. The deposit consists of east dipping units. Infill drilling has supported and refined the model and the current interpretation is considered robust. Outcrops of mineralisation and host rocks confirm the geometry of the mineralisation. Infill drilling has confirmed geological and grade continuity. |
Dimensions |
| The Rhyolite Ridge Mineral Resource area extends over a north-south strike length of 2,870m (from 4,183,750mN – 4,186,620mN), has a maximum width of 2,030m (423,730mE – 425,760mE) and includes the 550m vertical interval from 1,960mRL to 1,410mRL.. |
Estimation and modelling techniques |
| Using parameters derived from modelled variograms, Ordinary Kriging (OK) was used to estimate average block grades in three passes using Surpac software. Linear grade estimation was deemed suitable for the Rhyolite Ridge Mineral Resource due to the geological control on mineralisation. Maximum extrapolation of wireframes from drilling was 200m along strike and down-dip. This was half drill hole spacing in this region of the Project. Maximum extrapolation was generally half drill hole spacing. Reconciliation could not be conducted due to the absence of mining. It is assumed that boric acid and potassium sulphate can be recovered with lithium. In addition to Li; B, K, Ca, Mg, Fe and Al were interpolated into the block model. It is assumed that Ca and Mg are deleterious elements when considering the proposed processing methodology for the Rhyolite Ridge mineralisation. The parent block dimensions used were 100m NS by 50m EW by 5m vertical with sub-cells of 6.25m by 6.25m by 1.25m. The parent block size dimension was selected on the results obtained from Kriging Neighbourhood Analysis that suggested this was the optimal block size for the dataset. An orientated ‘ellipsoid’ search was used to select data and adjusted to account for the variations in lode orientations, however all other parameters were taken from the variography derived from domains 1 and 9. Up to four passes were used for each domain. The first pass had a range of 200, with a minimum of 10 samples. For the second pass, the range was extended to 400m, with a minimum of 6 samples. For the third pass, the range was extended to 1,000m, with a minimum of 2 samples. A fourth pass with an unlimited range and a minimum of 2 samples was required for a small number of blocks. A maximum of 20 samples was used for all four passes. No assumptions were made on selective mining units. Li had a reasonable positive correlation with Mg. Fe and Ca had a reasonable negative correlation. Remaining pairs had no correlations or weak correlations. The deposit mineralisation was constrained by wireframe surfaces constructed using a nominal 1,000ppm Li cut-off grade with a minimum down-hole length of 3m. For internal high grade B zones, a nominal 5,000ppm B cut-off grade was used. The wireframes were applied as hard boundaries in the estimate. Statistical analysis was carried out on data from seven domains. After review of the project statistics, it was determined that high-grade cuts for B within three mineralised domains was necessary. The cuts applied ranged between 300ppm and 11,000ppm B, resulting in 79 composites being cut. Validation of the model included detailed comparison of composite grades and block grades by northing and elevation. Validation plots showed good correlation between the composite grades and the block model grades. |
Moisture |
| Tonnages and grades were estimated on a dry in situ basis. |
Cut-off parameters |
| The Mineral Resource has been reported at a 1,050ppm lithium cut-off. The cut-off was selected based on an RPM cut-off calculator assuming an open pit mining method, a US$8,000/t Li2CO3 price, a 90% metallurgical recovery for Li2CO3 and costs derived from a high level technical report supplied by independent processing consultants to Global Geoscience and metallurgical test work results reported by Global Geoscience. Within the 1,050ppm lithium cut-off domain a sub-domain set at a cut-off of 0.5% boron was reported to define a zone of lithium-boron rich mineralisation within the Mineral Resource. |
Mining factors or assumptions |
| RPM has assumed that the deposit could potentially be mined using open cut mining techniques. No assumptions have been made for mining dilution or mining widths, however mineralisation is generally broad. It is assumed that mining dilution and ore loss will be incorporated into any Ore Reserve estimated from a future Mineral Resource with higher levels of confidence. |
Metallurgical factors or assumptions |
| Based on testwork completed for Global Geoscience by Hazen Research of Colorado, USA and SGS Minerals of Ontario, Canada and reported by Global Geoscience, both the lithium-boron and lithium-only mineralisation have a reasonable expectation of economic extraction. Global Geoscience is focussing its evaluation and testwork on the lithium-boron mineralisation as it potentially is of higher value with lower processing and capital costs. |
Environmental factors or assumptions |
| No assumptions have been made regarding environmental factors. Global Geoscience will work to mitigate environmental impacts as a result of any future mining or mineral processing. |
Bulk density |
| Various bulk densities have been assigned in the block model based on lithology and mineralisation. These densities were determined after averaging the density measurements obtained from diamond core. Bulk density was measured using the water immersion technique. Moisture is accounted for in the measuring process. A total of 137 bulk density measurements were obtained from core drilled at the Project. Bulk densities ranging between 1.8t/m3 and 2.11t/m3 were assigned in the block model dependent on mineralisation and lithology. It is assumed that the bulk density will have little variation within the separate material types across the breadth of the project area. |
Classification |
| The Mineral Resource estimate is reported here in compliance with the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves’ by the Joint Ore Reserves Committee (JORC). The Mineral Resource was classified as Indicated and Inferred Mineral Resource based on data quality, sample spacing, and lode continuity. The Indicated Mineral Resource was defined within areas of close spaced diamond and RC drilling of less than 200m by 200m, and where the continuity and predictability of the lode positions was good. The Inferred Mineral Resource was assigned to areas where drill hole spacing was greater than 200m by 200m and less than 400m by 400m. The input data is comprehensive in its coverage of the mineralisation and does not favour or misrepresent in-situ mineralisation. The definition of mineralised zones is based on high level geological understanding producing a robust model of mineralised domains. Validation of the block model shows good correlation of the input data to the estimated grades. The Mineral Resource estimate appropriately reflects the view of the Competent Person. |
Audits or reviews |
| Internal audits have been completed by RPM which verified the technical inputs, methodology, parameters and results of the estimate. |
Discussion of relative accuracy/ confidence |
| The lode geometry and continuity has been adequately interpreted to reflect the applied level of Measured, Indicated and Inferred Mineral Resource. The data quality is good and the drill holes have detailed logs produced by qualified geologists. A recognised laboratory has been used for all analyses. The Mineral Resource statement relates to global estimates of tonnes and grade. Reconciliation could not be conducted as no mining has occurred at the deposit. |